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This paper aims to propose an automatic and direct method to manipulate global parameters of the object for prototyping and simulation, given an STL mesh model of a thin-walled object. Proposed method is useful in rapid prototyping, where changing the global parameters such as thickness, scaling local features or draft of walls of an STL mesh is often required. Presently, user needs to iterate over the cycle of modification of the computer-aided design (CAD) model and tessellating it to change the global parameters. The proposed algorithm eliminates the need for CAD model while manipulating those global properties, as it works directly with the mesh model.

Proposed algorithm automatically identifies walls and its thickness, and then, it extracts mid-surface from each wall. Global parameters are then modified by using these mid-surfaces.

Mesh directly modified and the mesh obtained by tessellating modified CAD model has same global properties; proposed method can also allow multiple parameters to be modified at the same time.

Input STL model is assumed to be error-free, where models containing errors like self-intersection will lead to incorrect mid-surfaces. Present algorithm assumes that the mid-surface represent of the input STL model is a manifold surface.

A novel algorithm of directly manipulating global parameters of a thin-walled object in its STL mesh model is proposed. The paper also presents a novel method of extracting mid-surface representation from a thin-wall STL mesh.

This study proposes a new modified discrete preventive maintenance policy where failures of a system can be detected only by inspections and be fixed by minimal repairs. The maximum number of minimal repairs allowed to the system is, however, a prespecified integer, N. Under the proposed policy, inspections are conducted at times T, 2T, ...(T>0) to detect and fix failures by minimal repairs, and the whole system is preventively replaced by a new one when the cumulative number of failures detected becomes equal to an integer, k or more. The expected cost per unit time is formulated under the proposed maintenance policy. The existence of an optimal integer k=k* which minimizes the expected cost is then shown. Numerical examples are also presented to illustrate the theoretical underpinnings of the proposed formulation.

In this paper a method is presented for an efficient solution of the direct problem (find the scattered field for a given thin crack and driving field) in the time domain. This is a fundamental step in any non destructive evaluation problem. Two different approaches, one in the time domain and the other based on Fourier analysis, are used and compared with reference to a configuration for which some experimental results are available. The advantages and drawbacks of the two approaches are briefly discussed.

A simple neo‐classical theory of the demand for capital goods service is presented to clarify the relationship between the marginal productivity of capital and Keynes′s concept of the marginal efficiency of capital. How the latter concept is related to con‐temporary understanding of the marginal efficiency of investment is illustrated, while Keynes′s pessimism regarding stagnant investment is explained within the framework of neo‐classical theory.

Presents fundamental results on fuzzy Mealy machines. Unlike the classical Mealy machine which requires two functions, one to describe the next state and another to describe the output, a fuzzy Mealy machine requires only one fuzzy function to characterize completely the next state and the output produced. Apart from the obvious generalization that can be obtained from corresponding results on fuzzy finite state machines by introduction of an output associated with each transition, introduces the concept of an interval partition of [0, 1] and uses it to obtain more general results.

In this paper an outline of the development of methods for the analysis of non‐linear circuits is presented. Non‐inert and inert elements have been discerned and an inertia measure has been proposed. For this purpose, an exponential function with time constant T equal to T_R, T_L, or T_C is formulated for an element of type R, L, or C, respectively. In circuits with the imposed cause, which varies sinusoidally in time with period T_e, the following situations are distinguished and considered: T_e ≫ T; T_e ≪ T; and T_e ≈ T. In the first case, the effect changes in time according to the non‐linear characteristic of the element. In the second case, the respective circuit is referred to as the “quasi‐linear”, because for the sinusoidal cause the effect is also sinusoidal. In the third case, the hysteresis occurs and the effect is a two‐valued function. The hysteresis effect occurs also in resistive elements.

External corrosion prevention and control are addressed by coating/lining and cathodic protection (CP). Monitoring is usually by potential measurement using a standard half cell such as copper/copper sulphate or silver/silver chloride.

Ethics play an important role in society; however, many economics models assume that individual players act “economically” rational and ignore situations where an individual may forgo economic benefit for the public good. This chapter models the strategic interaction between auditors and management and allows for management to choose the economically irrational outcome of behaving ethically even when doing so defies their own financial self-interest. One of the model's assumption is that a certain percentage of managers do not engage in a “strategy” to misreport their financial statements because doing so is “unethical”. If recent accounting scandals are indicative of an ethical crisis in this country, this model offers hope because an increase in the percentage of unethical mangers leads to a decrease in fraudulent reporting. The model also illustrates the effects of an increase in the rewards for committing fraud (e.g., greater numbers of stock options, restricted stock, and accounting-based performance incentives) and an increase in the penalty for detected fraud (e.g., stiffer penalties for fraud from Sarbanes–Oxley).

The theory of pursuit games is obviously fragmentary at present. We know that general determinability of such games is incompatible with analysis, based on the principle of time continuity; but we also witness some reasonably successful probing on a smaller scale. The problem is one of existence of winning strategies for quite general sets and spaces. It will be shown here that in one case, where multivalued strategies are used, such strategies must necessarily be subclasses of Polish spaces and in the other, the monovalued case, the loser's set either has to be a first category set in the sense of Baire or an ideal, but in any case a kind of small set. This paper is meant to provide a common topological basis for the appreciation of more recent results.